This invention relates to vaporized fuel burners such as gasoline lanterns and camp stoves, and, more particularly, to a fuel control assembly for vaporized fuel burners which includes a single control member for operating the fuel flow valve, the orifice cleaner, and the inlet restricting member.
The invention is an improvement over the fuel control assembly for lanterns and stoves which is described in U.S. Pat. No. Re. 29,457 and Canadian Pat. No. 973,082 and the fuel control assembly for stoves which is referred to in the Declaration filed with U.S. Pat. No. Re. 29,457.
As described in said patents, vaporized fuel burners such as lanterns and camp stoves generally include a fuel tank, a fuel conduit including a generator tube, and burning means which is supplied with a mixture of fuel from the conduit and air. The generator tube is positioned adjacent the burning means so that fuel passing through the generator tube is vaporized, and a valve is interposed in the fuel conduit to open and close the fuel passage therethrough. A cleaner rod is usually mounted within the generator tube and is movable into and out of the discharge orifice of the generator to clean the orifice and, if desired, to regulate the flow of fuel therethrough. When the burning means is to be lighted and before the generator tube is heated sufficiently to vaporize the fuel, a restricting rod is used to restrict the flow of fuel into a chamber below a fuel tube to permit air to flow through the chamber and become entrained with the fuel passing into the fuel tube. This rod is removed from the fuel inlet when the generator is heated sufficiently to vaporize the fuel.
The fuel control assembly described in said patents and said Declaration utilizes a single control member for actuating the shut off valve, the generator orifice cleaner rod, and the inlet restricting rod in the proper sequence. Rotation of the control member from an off position to a clean position moves the cleaner rod into the generator orifice to clean the orifice; rotation of the control member from the clean position to a light position moves the cleaner rod out of the generator orifice, opens the shut off valve, and moves the restricting portion of the inlet restricting rod into the fuel inlet to restrict the flow of fuel and to permit the burner to be lighted; and rotation of the control member from the light position to a run position moves the restricting portion of the inlet restricting rod out of the fuel inlet to permit fuel to flow through the inlet unrestricted.
The foregoing fuel control assembly requires a number of separate parts which must be individually positioned within the valve body and which must at times move independently of each other. The shut off valve is a poppet-type valve which moves upwardly to its closed position as the cleaner rod moves upwardly toward the generator orifice. However, the valve reaches its closed position before the cleaner rod enters the generator orifice, and the cleaner rod must continue to move upwardly after the poppet valve has seated and has stopped moving. This requires a separate linkage between the poppet valve and the cleaner rod so that the poppet valve can be disassociated from further movement of the cleaner rod when the valve closes, a spring to maintain the valve closed, and a valve seat.
The separate, individual parts which are used in the assembly increase the cost of the assembly and require time and skill to be assembled properly. Further, the accumulated tolerances of the parts require the parts to be machined within close tolerances, resulting in additional costs. The poppet valve moves against a valve seat to shut off the fuel flow, and proper sealing might be prevented by machining chips, dirt, etc. which could lodge between the valve and the valve seat.